Forced circulation multiple unit air heating furnace



1951 I G. B. HERBSTER 2,564,479

FORCED CIRCULATION MULTIPLE UNIT AIR HEATING FURNACE Filed Jan. 7, 19482 Sheets-Sheet l O lll llllllll II II ll 2 I lIIIIlllllllllllgggmnna"INVENTOR. GEORGE E HER56 TE)? AWOIQ/VEYG,

Aug. 14, 1 5 G. B. HERBSTER FORCED CIRCULATION MULTIPLE UNIT AIR HEATINGFURNACE Filed Jan. 7, 1948 2 Sheets-Sheet 2 INVENTOR. 650/865 5.HEP/3575B ..tion of their extent.

Patented Aug. 14, 1951 TED STATES PA-TENT o-F erce FORCEDCIRCULATION'MUIZTIPIQEUN IT "AIR -HEATING FURNAGE 1 George-1L Herbster,Cleveland;.0hi0;sassjgnor; by mesne assignments, to8600,-.Denison,Company, Cleveland, Ohio, a corporation of ohioAppliczitionJanuary 7,194 s riamorszr .'.8 Claims. ll AThis inventionrelates toa heater and is an improvement, on, the heater disclosed andclaimed in myzco pending.applications Ser. No. 663,506, ,ifileid April19, '1946,-which application is "now aabandoned andSeru-No. 787,455,filed November "2 1, 1947.

,lIIl-JihflifilSt of "said: applications, therelis ,des- ,.cribed;.,,a-, heat ,exchangervcomprising a plurality qo'f, annular ,headsarranged in "a row I in spaced rface to facerelation from eachiother todefinejanz axialzcentral.passageand to define between v the; headsradial passages connected at their inner ends with the central passage.and open l at} their .outer .ends throughoutlthe' greater porcentrifugalradial discharge .blower -is arranged jzin .the central passage andreceives air from b,oth- ..ends and .dischargestitrradially of the headsthrough the radial passages into an enclosing wasing. ,In that-.structure, there .is va tendency,

ffor the, air discharged from the heads to. swirl about the .axis of thetcentral passagedn-lthe iradial passages ,anduin the interior of the,casing with the ,consequentlossaof eflicency in thevol- .urne'of airdischarged, from theca'sing .into the space? to be; heated.

" In my co pending application, Ser. .No. 787,455, the/casingrislmodifie'dufromthat of the earlier xapplicationto. provide "aspirally expandingpe- -=air impeller socombinedtherewith as to provideforan efficient and "better balanced-flow 70f air "in a-large volume inheat exchange -relationto the heat'exchangerand from the heat exchanger"into'the space tobe heated.

f'Other 'objects and advantages will 'become ap- "parent from thefollowing description wherein :r'eference made "to the drawings inwhich:

Figs-1 is-a side elevation of==a' heater embodying 'the" principles ofthe present invention;

-Fig. 2'is'a horizontal sectional view of the heater taken on the line2- -2"=in-Fig.1;

Fig. avertical section view of" the heater takenon line 3-' 3---o'f Fig.1.

A rotary impeller of a Re'ferring tol liiga 1, .2, ands-l3'the't-heatericomprises a heat exchanger whichiis spneferably formedof-a p1ura1ity-of annular'heat exchange heads I 'varranged in-arowin'axial alignment in spaced face to' facerelation to each-:otheraso asto define central passage 2 and "radial; passages '.:3'- which' connect:attheir inner endszwit-h the passaget'2 and'are open attheirxouterpends.

As morej'fully described in my'abovetsidentifiedtoo-pending"applications, each of the heads I ;-has 25a combustionchamber portion-Wand stack-sportion '5, the .former rof which is open atits lower end into.:a burner compartment-6. A" gas burner I sisrarrangedin the ,compartmentjG 'and; hasa,

iplurality .of head rportions -whichdischarge into thercombustionchamber portions 4; respectively,

-' of the heads" I Oil burners-likewise may :be: used. Thus, each head,including its combustion-chamber portion .4; and: stackportion; 5 isspaeedflatwise of" the heads-from the heads adjacentthereto :;overgtheentire extent of its side-wallsso that, :except lfOI -a slight-blocking'by the burnertcompartment top wall and bytheaccumulatinghead forthestackport-ions, the radial passages formed between the headsrare open,fully to "the atmosphere at theouterperipheries of the :heads foriltheir entirelperipheral extent.

The heater heads I. .are enclosed-in a: suitable casing. '8which-preferabl-yyhas-a spiral peripheral wall-9,-and.outlet I 0- such'as described in myrcopending application Ser; No. 787,455. Thecasing.l8ihaszendwalls- I I which are spaced axially, from -the,outermost.heads lot the row of headsland have central openings I2 co-axialWiththe-central passage! but of less diameter lthan'the passage v2.

.Mountedonthe side walls of the ..casing.= are ,suitablewbrackets l3whichrsupport, a rotatable shaftv I4 drivenby; means .of a pulley vl5,,beltl 6, .and. motor I1. .Mounted on the. shaft I4 between vadjacentheads I and betweentheend heads of the row andtheadjacentside ,wallsIIaresectionso'f arotary, centrifugal radial discharge .iblower-iimpeller..Since each, of the impeller sections is the same in form andfunction,one only wilLbe described in detail.

iAs illustrated in Fig. 2,7the impeller section at "the extreme-rightcomprises ahub I8 mounted on theshaft M .for rotation therewith and asuit- ;able spider'IS'to the outer ends of which "are connecteda'plurality-of impellerbladesZU. f The impeller bladespreferably arearrangedjgenerally -;paralleltothe axis or the shaft Idand'are spacedapartcircumferentially g in the usual manner so =that upon*rotationp-airis drawn in axially of the impeller and discharged"centrifugallyradially therefrom. The impellers between adjacent heads are similar tothe impeller described except that they are slightly shorter and allimpellers are preferably of the same diameter. The extra length of theimpellers between the walls II and the end heads of the row is provideddue to the fact i1that they must initiate any inward flow of a Usuallywhen such impellers operate to draw in air from an adjacent air masswhich is relatively static, the first inch or so axially from the inletis not as eiiective for drawing in and discharging air as is theremainder of the length of the blades because the air is already inmotion axially of the impeller as to said remainder of the length of theblades. Consequently, the blades 20 inwardly, axially of the impellerfrom the ends of the impeller may be shorter than those blades which areat the ends of the impeller as generally the air is already in motionaxially of the impeller when it reaches the planes of the radialpassages between the heads.

It will be noted from Fig. 2 that the impeller blades are closelyconfined between the heads and between the side walls and adjacent headsso as to prevent a return of air toward the axis of the impellersections around the ends of each impeller section. Furthermore, theimpeller blades are spaced outwardly beyond the major portion of theradial length of the heating heads so that the air drawn in by theimpeller sections is caused to pass into heat exchange relation to theheads before it reaches the blades except for the radially outermostextremities of the heads. Due to the much larger diameter of theimpeller relative to the heads in the present form of the invention, ascompared to the form shown in my co-pending applications, the impellermay be rotated at considerably slower angular speeds for the same volumeof air, thus reducing vibra tion and also reducing eddy-currents betweenthe heads. In fact, the volume of air delivered is very greatlyincreased over' that obtainable with equal size heat exchange headsusing an impeller of the diameter of the central passage Thus a betterbalance between heat exchange surface, volume of air and time ofexposure of the air to the surface is obtained.

The impeller sections provide an impeller means between the axis andblades of which the major portion of the heat exchange means isdisposed. The structure above described is particularly suitable forspace heaters and central furnaces.

Having thus described my invention, I claim:

1. A heat exchanger and blower combination comprising a plurality ofupright substantially annular disc-like hollow heat exchange headsarranged in a row in axial alignment and spaced face to face relationand defining a central axial passage with generally annular radialpassages between adjacent faces of the heads and connected to andradiating from the centralpassage, each of said heads having acombustion chamber portion at its lower portion and an exhaust portionat its upper portion, said combustion chambar and exhaust portions ofeach head being spaced apart endwise of the row from the correspondingportions of adjacent heads and each head having at least one passageextending clockwise, and at least one passage extending counterclockwiseabout the central passage from the combustion chamber portion to theexhaust portion, rotary blower impeller sections coaxial with thecentral passage and extending radially outwardly from the centralpassage into said radial passages, respectively, and arranged to receiveair axially, and means supporting said sections for rotation about theaxis of the central passage.

2. A combination according to claim 1 characterized in that each of saidsections has a plurality of impeller vanes spaced radially outwardlyfrom its axis of rotation nearly to the outer peripheral limits of theheat exchange heads.

3. A combination according to claim 1 characterized in that said headshave annular wall surface portions disposed close to the ends of thesections for constraining air passing between adjacent heads to passbetween the end limits of the impeller section which is between theheads.

4. A heat exchanger and blower combination comprising a plurality ofupright generally annular disc-like hollow heat exchange heads ar rangedin a row in axial alignment and in face to face spaced relation anddefining a central passage and defining between adjacent heads radialpassages which are connected at their inner ends to the central passage,each of said heads having a combustion chamber portion at its lowerportion and an exhaust portion at its upper portion, said combustionchamber and exhaust portions of each head being spaced apart endwise ofthe row from the corresponding portions of adjacent heads and each headhaving at least one passage extending clockwise, and at least onepassage extending counterclockwise about the central passage from thecombustion chamber portion to the exhaust portion, a casing enclosingthe heads and having a front wall and rear wall spaced from the ends ofthe row of heads, respectively, said walls having air inlet passagesaligned with the central passage, centrifugal blower impeller sectionsin the radial passages, and between the end heads of the row and saidwalls, respectively, said sections being coaxial with the centralpassage and having their outer peripheries radially outwardly beyond theinner periphery of the heads, means supporting the impeller sections forrotation about the axis of the central passage, and said casing having adischarge opening spaced from the inlet openings.

5. A heater comprising a plurality of upright, substantially annulardisc-like hollow heating heads arranged in a row in axial alignment andflatwise spaced relation to each other and providing a central axialpassage and generally an nular radial passages between adjacent headsand leading from the central passage and open at their outer limits,each of said heads having a combustion chamber portion at its lowerportion and an exhaust portion at its upper portion,

the said combustion chamber and exhaust portions of each head beingspaced apart endwise of the row from the corresponding portions ofadjacent heads, each head having a plurality of passages thereinextending circumferentially of the heads in opposite directions from itscombustion chamber portion to its exhaust portion, burner means tosupply combustible media into the combustion chamber portions, rotaryimpeller means coaxial with the central passage and includingcircumferentially extending rows of impeller blade portions in alignmentradially with the radial passages, said rows of blade portions beingcoaxial with the row of heads and disposed radially outwardly from theaxis at least beyond the inner periphery of the heads.

6. A heater according to claim 5 characterized in that the bladeportions are between the heads.

7. A heater according to claim 5 characterized in that said impellermeans includes a rotatable shaft coaxial with and extending into thecentral passage and supporting means for the blade portions carried bythe shaft and extending radially outwardly through the radial passages.

8. A heater according to claim 5 characterized in that said heads areimperforate between their inner and outer radial limits.

GEORGE E. HERBSTER.

REFERENCES CITED The following references are of record in the file ofthis patent:

Number Number 6 UNITED STATES PATENTS Name Date Le Grand Sept. 20, 1932Redfield Nov. 5, 1935 Cummings, Jr. Apr. 22, 1941 Bergstrom Mar. 10,1942 FOREIGN PATENTS Country Date France May 8, 1923

